1. Field of the Invention
This invention relates generally to the reading of non-legible information appearing on a credit card or similar article. In particular, this invention relates to the reading and processing of non-legible information appearing in the form of magnetic recordings on a credit card or similar article.
2. Description of the Prior Art
The processing of non-legible information appearing on articles such as personalized cards in the hands of the general public has been continually expanding in the recent past. This non-legible information has usually taken the form of either an optical bar encoding or a magnetic recording. In either instance, the non-legible information is in a form that can be detected by appropriate data processing equipment. While both forms of non-legible information are in use, it is to be appreciated that the magnetically recorded form results in a significantly increased recording density. This is quite important when one realizes that the non-legible information is usually confined to a relatively small area on the card.
There are basically two ways of reading magnetically recorded information appearing on a card or similar article. One way is to move the card relative to a magnetic head so as to cause the magnetic field to vary underneath the head. Another way is to maintain the card in a stationary position and move the magnetic head relative thereto so as to create a varying magnetic field underneath the read head. In either instance, it is common practice to initiate the relative movement by a motorized means which is often part of an overall servo control. This type of controlled motion provides for a constant relative movement that can be relied upon in reading the recorded information. While this increases the accuracy of reading the recorded information, the same is nonetheless accomplished at great expense. In this regard, the provision of a small motorized means which is subject to servo control can result in elaborate electrical circuitry and mechanical parts.
Attempts have been made to eliminate the need for a constant relative movement. These attempts have often lead to elaborate circuitry to compensate for any variation in speed experienced in the relative movement between the card and the magnetic head.